rfc-1918 reverses broken again (still?)

The reverse lookups for the RFC-1918 address space are broken again, or

$ dig -x 172.16 any @blackhole.isi.edu

; <<>> DiG 8.1 <<>> -x any @blackhole.isi.edu
; (1 server found)
;; res options: init recurs defnam dnsrch
;; res_send to server blackhole.isi.edu Connection timed out

  Its a busy machine. It does not help that an increasingly large
  number of machines are attempting to dynamically update the zones.


Then I'm afraid I have to question why the machine is being used if it is
apparently completely incapable of handling the load being placed on it,
and why the other name servers in question (ns2 and rs0.internic.net) give
bogus responses, when they respond.

I'm sure you could find a provider willing to donate a machine that can
handle the load. I'm sure having more than one functioning server (if it
is, as you say, functioning since I can't find any evidence of that...)
would help too.

This has been an ongoing long term problem and it would be nice to see it
actually fixed some day.